1. Field of the Invention
The present invention relates to a testing system and a testing method using a loading mechanism which applies a desired load quantity on a test body, and in particular, to a multiple testing system and a testing method which carry out testing in parallel by using plural testing units.
2. Description of the Related Art
Conventionally, evaluation of the fatigue life of the test body is carried out by loading on test bodies using a fatigue testing device. In recent years, there has been the demand to carry out evaluation of the fatigue life in an ultra-high cycle regime exceeding 107 cycles. However, carrying out fatigue testing in an ultra-high cycle regime requires a long period of time.
In order to shorten the time required for fatigue testing, there is known a fatigue testing unit 110 such as that shown in FIG. 8 which effects control such that cyclic loading of a load on a test body is carried out at high speed. On the basis of an instruction from a computer 118, a servo amplifier 113 is controlled by a microcomputer 120 of a high speed controlling device 116, and a test waveform is outputted to a servo valve which carries out supply and adjustment of the flow rate of hydraulic fluid to a hydraulic actuator of a fatigue testing unit 112.
Because statistical evaluation is essential in order to evaluate the fatigue life in such an ultra-high cycle regime, a fatigue test must be carried out multiple times under the same load conditions, and the fatigue testing requires even more time.
In order to further shorten the time required for fatigue testing, carrying out testing in parallel by using plural fatigue testing units has been proposed. There is known a multiple fatigue testing unit system in which a single hydraulic power source is used in common for plural fatigue testing units, and the supply lines to the respective fatigue testing units are connected to an oil tank and a hydraulic pump which serve as the single hydraulic power source (Japanese Patent Application Laid-Open (JP-A) No. 2003-75315).